Over the weekend, a friend of mine greeted me with a sardonic question.

"So, how does it feel to live in a state of emergency?" he wondered.

"About the same as it did to live in a couple dozen states of emergency last week," I replied.

Like most Americans, my friend didn't know just how common presidential declarations of emergency are — nor how enduring they turn out to be.

Members of Congress spent much of the last week declaring themselves similarly shocked over President Trump's declaration of emergency at the southern border. Most of the critics expressed their shock at seeing Trump ignore congressional authority over the power of the purse. "Declaring a national emergency would be a lawless act," Senate Minority Leader Chuck Schumer (D-N.Y.) said from the Senate floor, pledging to challenge the action in court. "We should not set the terrible precedent," argued Sen. Chris Coons (D-Del.), "of letting a president declare a national emergency simply as a way of getting around the congressional appropriations process."

Unfortunately for Coons and other Democrats — and a handful of Republicans protesting Trump's actions — that precedent was set decades ago. While this may be the first time a president has used the National Emergencies Act passed by Congress in 1976 to bypass Congress' appropriations process, the law does indeed contain a grant of authority for presidents to spend money without appropriation from Congress. If Congress challenges Trump's novel use of the NEA, it might have to explain why the law allows for his move in the first place — and why Congress remained uninterested in policing this authority until now.

It's unclear why Congress felt it necessary in our bicentennial year to devolve these emergency powers to the executive branch. Before the modern transportation era, Congress might have legitimately worried about coming into session quickly enough to authorize expenditures and pass statutes to deal with genuine emergencies. By 1976, however, Congress had long established year-round sessions, and its members were never more than hours away from Washington, D.C.

The grant of executive authority in the NEA is not merely ceremonial. The Brennan Center found well over 100 statutory powers that become active for presidents under national emergencies. One in particular speaks directly to Trump's ambition for a border wall: 10 U.S.C. 2808, which addresses the use of Department of Defense resources. It says that "Secretary of Defense, without regard to any other provision of law, may undertake military construction projects, and may authorize secretaries of the military departments to undertake military construction projects, that are necessary to support such use of the armed forces."

Both Bushes cited this authority in emergencies declared during their tenures. The late President George H.W. Bush used it in November 1990 to mobilize after the Iraqi invasion of Kuwait, and former President George W. Bush used it after 9/11. This authority allowed both presidents to ignore the current defense appropriation from Congress and spend the money as they saw fit — even though Congress in both instances was in session and could have speedily dealt with the issues by passing authorization for such actions.

Those two examples do stand out as genuine emergencies, as does the first declaration regarding Iran and the hostage crisis in 1979 by then-President Jimmy Carter. Trump's critics claim that the southern border doesn't amount to a crisis, let alone an emergency. Unfortunately for those critics, the use of this authority has mainly been for such non-emergency purposes. Until now, Congress not only hasn't objected to the use the NEA for purposes that could easily have been addressed under normal conditions — such as applying sanctions in Belarus in 2006 — it hasn't had much interest in using its authority to close out emergencies and restore its own standing.

Regulation of the Anchorage and Movement of Vessels with respect to Cuba (1997)

Prohibiting Certain Transactions with Respect to the Development of Iranian Petroleum Resources (1995)

Blocking Sudanese Government Property and Prohibiting Transactions with Sudan (1997)

Blocking Property of Persons Who Threaten International Stabilization Efforts in the Western Balkans (2001)

In all, we were living in 31 concurrent states of emergency even before this latest declaration. Of the 28 emergencies no longer in effect, not a single one was revoked by an act of Congress. Successive Congresses have been content to let presidents decide when to surrender their increased authority … or let them keep it. Why? Because members of Congress find it easier to punt this responsibility to the executive branch than roll up their own sleeves to deal with mainly mundane issues.

It's going to be tough for Congress to argue in court that it's concerned about its constitutional privilege after decades of ignoring it. If members of Congress want to be taken seriously about the separation of powers, they can start by repealing the NEA. Or at least start taking steps to close down the other 31 states of emergency.

If Congress insists on passing the buck to the executive branch, it can't profess shock and incredulity when a president finally spends it.